Hi all,
I have 2 tables, with a 1-n relation:
parent( oid, parent_name)
child(oid, child_name, iod_parent)
How do I get the parent_names of all parents without a child?
select parent_name from parent
left join child on (parent.oid=child.iod_parent)
where child.oid is null;
or
select parent_name from parent
where not exists (select * from child where
child.iod_parent=parent.oid);
Regards,
Tomasz Myrta
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